/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.

Quake III Arena source code is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Quake III Arena source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/

#include "../qcommon/q_shared.h"
#include "../qcommon/qcommon.h"
#include "sys_local.h"

#define MAX_LOG 32768

static char     consoleLog[MAX_LOG];
static unsigned int writePos = 0;
static unsigned int readPos = 0;

/*
==================
CON_LogSize
==================
*/
unsigned int CON_LogSize(void)
{
	if(readPos <= writePos)
		return writePos - readPos;
	else
		return writePos + MAX_LOG - readPos;
}

/*
==================
CON_LogFree
==================
*/
static unsigned int CON_LogFree(void)
{
	return MAX_LOG - CON_LogSize() - 1;
}

/*
==================
CON_LogWrite
==================
*/
unsigned int CON_LogWrite(const char *in)
{
	unsigned int    length = strlen(in);
	unsigned int    firstChunk;
	unsigned int    secondChunk;

	while(CON_LogFree() < length && CON_LogSize() > 0)
	{
		// Free enough space
		while(consoleLog[readPos] != '\n' && CON_LogSize() > 1)
			readPos = (readPos + 1) % MAX_LOG;

		// Skip past the '\n'
		readPos = (readPos + 1) % MAX_LOG;
	}

	if(CON_LogFree() < length)
		return 0;

	if(writePos + length > MAX_LOG)
	{
		firstChunk = MAX_LOG - writePos;
		secondChunk = length - firstChunk;
	}
	else
	{
		firstChunk = length;
		secondChunk = 0;
	}

	Com_Memcpy(consoleLog + writePos, in, firstChunk);
	Com_Memcpy(consoleLog, in + firstChunk, secondChunk);

	writePos = (writePos + length) % MAX_LOG;

	return length;
}

/*
==================
CON_LogRead
==================
*/
unsigned int CON_LogRead(char *out, unsigned int outSize)
{
	unsigned int    firstChunk;
	unsigned int    secondChunk;

	if(CON_LogSize() < outSize)
		outSize = CON_LogSize();

	if(readPos + outSize > MAX_LOG)
	{
		firstChunk = MAX_LOG - readPos;
		secondChunk = outSize - firstChunk;
	}
	else
	{
		firstChunk = outSize;
		secondChunk = 0;
	}

	Com_Memcpy(out, consoleLog + readPos, firstChunk);
	Com_Memcpy(out + firstChunk, out, secondChunk);

	readPos = (readPos + outSize) % MAX_LOG;

	return outSize;
}
